@@ -27,6 +27,58 @@ static const char smc_lo_dev_name[] = "loopback-ism";
static struct smc_lo_dev *lo_dev;
static struct class *smc_class;
+static int smcd_lo_register_dev(struct smc_lo_dev *ldev);
+static void smcd_lo_unregister_dev(struct smc_lo_dev *ldev);
+
+static ssize_t active_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct smc_lo_dev *ldev =
+ container_of(dev, struct smc_lo_dev, dev);
+
+ return sysfs_emit(buf, "%d\n", ldev->active);
+}
+
+static ssize_t active_store(struct device *dev,
+ struct device_attribute *attr,
+ const char *buf, size_t count)
+{
+ struct smc_lo_dev *ldev =
+ container_of(dev, struct smc_lo_dev, dev);
+ bool active;
+ int ret;
+
+ ret = kstrtobool(buf, &active);
+ if (ret)
+ return ret;
+
+ if (active && !ldev->active) {
+ /* activate loopback-ism */
+ ret = smcd_lo_register_dev(ldev);
+ if (ret)
+ return ret;
+ } else if (!active && ldev->active) {
+ /* deactivate loopback-ism */
+ smcd_lo_unregister_dev(ldev);
+ }
+
+ return count;
+}
+static DEVICE_ATTR_RW(active);
+static struct attribute *smc_lo_attrs[] = {
+ &dev_attr_active.attr,
+ NULL,
+};
+
+static struct attribute_group smc_lo_attr_group = {
+ .attrs = smc_lo_attrs,
+};
+
+static const struct attribute_group *smc_lo_attr_groups[] = {
+ &smc_lo_attr_group,
+ NULL,
+};
+
static void smc_lo_generate_id(struct smc_lo_dev *ldev)
{
struct smcd_gid *lgid = &ldev->local_gid;
@@ -282,6 +334,7 @@ static int smcd_lo_register_dev(struct smc_lo_dev *ldev)
mutex_lock(&smcd_dev_list.mutex);
list_add(&smcd->list, &smcd_dev_list.list);
mutex_unlock(&smcd_dev_list.mutex);
+ ldev->active = 1;
pr_warn_ratelimited("smc: adding smcd device %s\n",
smc_lo_dev_name);
return 0;
@@ -293,6 +346,7 @@ static void smcd_lo_unregister_dev(struct smc_lo_dev *ldev)
pr_warn_ratelimited("smc: removing smcd device %s\n",
smc_lo_dev_name);
+ ldev->active = 0;
smcd->going_away = 1;
smc_smcd_terminate_all(smcd);
mutex_lock(&smcd_dev_list.mutex);
@@ -340,6 +394,7 @@ static int smc_lo_dev_probe(void)
ldev->dev.parent = NULL;
ldev->dev.class = smc_class;
+ ldev->dev.groups = smc_lo_attr_groups;
ldev->dev.release = smc_lo_dev_release;
device_initialize(&ldev->dev);
dev_set_name(&ldev->dev, smc_lo_dev_name);
@@ -35,6 +35,7 @@ struct smc_lo_dmb_node {
struct smc_lo_dev {
struct smcd_dev *smcd;
struct device dev;
+ u8 active;
u16 chid;
struct smcd_gid local_gid;
rwlock_t dmb_ht_lock;
This provides a runtime switch to activate or deactivate loopback-ism device by echo {1|0} > /sys/devices/virtual/smc/loopback-ism/active. It will trigger the registration or removal of loopback-ism from the SMC-D device list. Signed-off-by: Wen Gu <guwen@linux.alibaba.com> --- net/smc/smc_loopback.c | 55 ++++++++++++++++++++++++++++++++++++++++++ net/smc/smc_loopback.h | 1 + 2 files changed, 56 insertions(+)